The present invention generally relates to the field of refrigeration and more specifically to devices, apparatuses and systems used to refrigerate enclosed structural spaces of the type often referred to as walk-in freezers or walk-in coolers. More particularly, the invention relates to such devices that are electrically powered and comprise compressor, condenser and evaporator components, wherein the compressor circulates a refrigerant such as Freon gas, delivering the refrigerant in liquid state at high pressure to the condenser where the temperature is reduced, typically by passing air over the condenser. The refrigerant is then drawn into the evaporator, where it evaporates or expands into a gas state and absorbs heat from the air to be cooled, before being drawn back into the compressor for condensing and recirculation.
Most refrigeration systems do not provide a backup mechanism or redundant means for cooling a space that can be utilized when the primary system fails. The cost of such backup systems is typically too prohibitive to provide such a system for each cooler or room. Where redundant systems exist, they are integral components of the cooler or room and are not portable in any manner. Furthermore, such backup systems rely on the same high power circuits as the primary system and are thus useless in situations where the problem is a failure of the power supply rather than a mechanical failure of the primary system.
In many circumstances failure of the refrigeration system for an extended length of time results in the loss of valuable commodities, such as for example food that must be destroyed due to defrosting or warming. Likewise, there are circumstances where hazardous materials, irreplaceable items or other valuable temperature-sensitive items must be maintained at reduced temperature.
Thus, there exists a need for a redundant or secondary refrigeration system that can be utilized to maintain a refrigerated space below a desired temperature when the primary refrigeration system fails or loses power. Ideally, the secondary system is portable and can be utilized with or without retrofitting the refrigerated space. Furthermore, it is desirable that the secondary system operates from standard 115 volt power sources, whether in the form of standard outlets located within or near to the refrigerated space or a gas powered generator.
Additionally, it is often desirable to temporarily cool a room or space that has no primary refrigeration means. Thus, there exists a need for a portable refrigeration system that can be utilized to create a refrigerated space.
It is an object of this invention to provide a modular portable refrigeration unit that addresses the expressed problems, needs and desires and well as possible additional problems, needs and desires that will become obvious after review of the following disclosure. It is a further object of this invention to provide such a refrigeration unit wherein the evaporator means of the refrigeration unit can be physically distanced from the condenser means comprising the compressor and condenser while remaining in fluid communication through lengths of flexible hoses, such that the evaporator means can be positioned within the refrigerated space to be cooled, while the condenser means remains external to the refrigerated space. It is a further object to provide such a refrigeration unit wherein the evaporator means can be temporarily disconnected from the condenser means during relocation into the refrigerated space without loss of refrigerant, then easily reconnected to perform the cooling operation.